It is Tuesday night, and immigration officials and airport staff are preparing for the impending departure of one VIP - with two red carpets.
Four passenger jets sit on the tarmac at Changi Airport's VIP complex: two Air China Boeing 747s and two Air Koryo Ilyushins.
No one knows which plane North Korean leader Kim Jong Un would take to go home. No one knows what time he would leave.
Eventually, the Singapore staff make a calculated guess, unfurl two red carpets, each leading to one Air China plane - and pray that he is taking either one of them.
"We just had to hope and pray that he was not going to go on the other planes. It's a very sensitive thing, and these red-carpeted boarding steps cannot be easily moved," says Immigration and Checkpoints Authority (ICA) Inspector Reshma Nair, 33.
In the end, to their relief, Mr Kim did take one of the two, finally leaving Singapore at around 11.30pm.
Such was the secrecy of the visiting North Korean delegation, a factor that generated a fair bit of last-minute scrambling in what is usually a thoroughly choreographed political affair.
While Singapore is an old hand at hosting high-level summits, the June 12 meeting between United States President Donald Trump and Mr Kim was unparalleled in the level of challenges it posed.
Besides the unknown and unpredictable North Korean factor, there was the compressed timeframe for preparations and the sensitive nature of the meeting.
In the end, the Republic managed to pull it off, though not without some near heart attacks away from the international media's glare, officials involved say.
How did they do it?
Insight pieces it together.
The primary benefit is that we helped on the path to peace. That is in the interest of the world, it is in the interest of the region and specifically in the interest of Singapore. I don't think you can put a dollar value on that.
HOME AFFAIRS AND LAW MINISTER K. SHANMUGAM, who was a former foreign minister.
ON OR OFF?
The Cabinet first had an inkling that Singapore could be asked to host the summit in early May, when US officials first broached the possibility.
But it was "without any clarification and certainty, and you know we can't go on the basis of possibilities", says Home Affairs and Law Minister K. Shanmugam in an interview.
At the same time, countries from Mongolia to Switzerland were being thrown up as possible locations.
Then, on May 10, Mr Trump tweeted that the summit would be held in Singapore on June 12.
But just as abruptly as this was announced, the meeting was cancelled on May 24, only to be reinstated two days later.
By then, Singapore had been formally approached to host it, but because of the on-off-on plans, "we unscrambled everything, then we had to scramble again", says Mr Shanmugam.
The matter was discussed at the Cabinet level. "We agreed that we should host. The considerations were that this was a request made by both sides to us and it is helpful in the peace process," he adds.
It was a unanimous decision, though the Cabinet did contemplate the "downsides" to it.
He did not elaborate on these.
"It's primarily a question of principle. It is the right thing to do, it is a good thing for regional security, international security, and it benefits Singapore in a strategic way because it enhances our well-being as a country and a people."
In the end, preparations started in earnest just slightly more than two weeks to the summit date.
The effort was spearheaded by inter-ministerial teams led by the Ministry of Foreign Affairs (MFA).
The Home Affairs, Defence, Communications and Information, and Transport ministries also played key roles.
At least 7,400 public officers were roped in. They included 5,000 from the Home Team, 2,000 from the Singapore Armed Forces (SAF), over 300 information officers and 80 officers from the MFA.
This was similar in scale to the IMF-World Bank meetings that Singapore hosted in 2006 and which took over five years to plan. Back then, 8,000 public officials and 2,000 volunteers were involved.
This time, working within the short timeframe was "a bit of a mission impossible", recalls Mr Jimmy Toh, 46, who was in charge of getting a media centre up and running for over 2,500 journalists who covered the event.
"We went around, a bit like real estate agents, exploring all the hotels, convention halls. For those that were big enough, they were occupied. For those that were ideal, they didn't have the capacity to take in the numbers.
"There was quite a fair bit of disappointment along the way," says Mr Toh, senior director of engagement at the Ministry of Communications and Information (MCI).
In the end, officials hit on the idea of converting the F1 Pit Building into a media centre.
The bulk of MCI's spending - which The Sunday Times understands amounted to $5 million or so - went to this.
It took a whole-of-government effort to pull things off. Among those who handled the media were people from across 10 ministries, including teachers and policy officers.
Inter-agency cooperation also helped ensure smooth immigration clearance of the US and North Korean delegations, says Insp Nair.
There were hundreds of visas to process in just two weeks. To get it done, ICA worked with the MFA, Singapore Customs, the police and bodies such as the Civil Aviation Authority of Singapore.
FROM TOILETS TO A LAST-MINUTE TOUR
As it turned out, the uncertainty faced by the airport staff on Tuesday was a theme that ran throughout the summit, from the time the leaders arrived last Sunday.
This was largely due to the lack of trust on both sides, and the sensitivity of the meeting: It was the first between a serving US president and a North Korean leader, whose countries are technically still at war.
The lack of familiarity with the North Koreans, who are famously paranoid about secrecy and security, added another level of complexity to the preparations.
Unlike with the US, where there is already a well-established set of practices, there were no past bilateral visits to model on for hosting Mr Kim, says MFA's chief of protocol Ong Siew Gay, whose team was in charge of ensuring the correct etiquette was followed in interactions with the two visiting leaders.
Erring on the side of caution, Mr Ong made sure to mention even the tiniest details to his North Korean counterpart in running through the visit. There was no telling what could offend Mr Kim, or if something would pose a security concern, and he did not want to leave anything to chance, he adds.
One such detail was the signing of the guest book at the Istana before Mr Kim's bilateral meeting with Prime Minister Lee Hsien Loong last Sunday.
A draft with the inscription of Mr Kim's name was handed in advance to the North Koreans for them to check that the title - Chairman of the State Affairs Commission of the Democratic People's Republic of Korea - was acceptable.
Effort was also made to explain how exactly the signing ceremony would play out - for instance, who else would be around.
Just this short sequence required two or three rounds of back-and-forth before a plan was settled on.
Language also posed a barrier.
There was only one North Korean representative who spoke good English designated to liaise with Mr Ong and his team.
The same issue cropped up for the officers working on security.
SAF Third Warrant Officer Terrence Lee, team commander-in-charge of the security sweep of the Capella Singapore where the summit was held, recounts how he resorted to hand gestures to communicate with the North Korean security team as they combed the hotel grounds together.
"We would give the North Koreans hand signals, like 'OK' or 'let's move on'," he says, gesticulating to Insight.
From the security perspective, North Korea was also an "unknown partner", says the police force's director of operations How Kwang Hwee, 39.
"We had to start to understand and learn from them in terms of how they work," he adds. "Because they are operating in Singapore, they also have to work in a way that meets our requirements."
Many discussions took place, going through the various points of deployment, "agreeing, disagreeing, changing the way we deploy" officers.
The North Korean leader is famously worried about assassination, and his officials baulked even at the equipment of journalists covering the event, concerned that the cameras could be concealed weapons, the Associated Press reported.
Besides his jogging bodyguards, Mr Kim had other unusual security requirements.
Insight understands these included special requests for him not to be photographed entering his vehicle. He had also flown in his own food, and is said to have needed a special area for his cooks to prepare his meals.
Keeping plans under wraps is a standard practice in protecting leaders, but most of Mr Kim's schedule was shrouded in secrecy, and revealed at the very last minute even to the Singapore authorities.
His decision to tour Marina Bay Sands, Gardens by the Bay, Jubilee Bridge as well as the Pasir Panjang port facilities on Monday night, for instance, was unexpected.
The request was made just a few hours before.
This posed a challenge to the police and the SAF that had to secure the landmarks and the route his motorcade would take before his visit.
Selected locations also had to be swept for chemical, biological, radiological and explosive threats.
The late confirmation of essential details for the summit itself posed the biggest challenge to securing it, says Chief of Defence Force Melvyn Ong.
Information such as key locations was confirmed just a week before it began. Even then, the exact plans and requirements of both countries were not clear until the security forces later met up with advance parties from both sides.
On the US side, Mr Trump is also one of a small number of people in the world with the highest security classifications.
He, too, was a volatile personality. The Washington Post reported that after he arrived in Singapore last Sunday, Mr Trump, feeling antsy and bored, had wanted his officials to move the long-planned meeting forward by a day, to Monday.
"We're here now. Why can't we just do it?" he reportedly asked, before being talked out of the idea.
It left some on the US side fearful that the summit might be scuttled, said the Post, quoting two people familiar with preparations.
The US officials later credited the Singapore Government for helping to prevent the mistrust on both sides from jeopardising the summit, the AP reported.
Commenting on the security operations, Mr Shanmugam says: "If we couldn't guarantee the safety and security of the American President or Chairman Kim, there would have been no summit.
"It's because they believed that we could guarantee that they agreed, and of course we then had to go ahead and make sure that it worked."
MEETING OF TWO EQUALS
Some had bristled at Mr Trump and Mr Kim meeting as equals during the summit, saying it legitimised the North Korean regime accused of running concentration camps and executing hundreds of people.
But as host, Singapore was told by both delegations "that there ought to be as much as possible optical parity", says Mr Ong. The North Koreans were especially emphatic about this, he adds.
So, whether it was motorcade arrangements, the receiving party at the airport or the hotels they stayed in, the treatment had to be equal.
For instance, when it looked like the US delegation was likely to stay in the Shangri-La Hotel, Singapore helped an advance North Korea team narrow their search to somewhere comparable.
In the end, the North Koreans settled on The St Regis Singapore.
Both leaders were received by Foreign Minister Vivian Balakrishnan at the airport.
Each of their motorcades also had about 40 vehicles in the main convoy, with Singapore having supplied some armoured vehicles to the North Korean delegation for use.
On Singapore's part, it also meant offering both leaders the same meetings and meals. Both delegations were told that PM Lee could either host a lunch or dinner on top of their bilateral meetings, but North Korea decided that it did not have time for a meal, and went with just a meeting, says Mr Ong.
Singapore, meanwhile, paid for the North Korean delegation's hotel stay, though not for the Americans who paid their own way, as is the norm for such bilateral events hosted by a third party.
This attracted some flak.
A wefie taken by Dr Balakrishnan and Education Minister Ong Ye Kung with Mr Kim during his city tour also raised questions about whether the two Singapore ministers had crossed the line in being too chummy with him.
Asked about these criticisms, MFA's Mr Ong declines comment, saying only that it is not uncommon for Singapore to foot the hotel bill when leaders are here on state visits.
Those interviewed did not want to say how much Singapore paid this time. But the 3,600 sq ft presidential suite where Mr Kim stayed costs about $10,000 a night.
This was part of the total $20 million bill that Singapore footed for hosting the summit.
By comparison, the IMF-World Bank meetings cost Singapore about $130 million.
WIN FOR SINGAPORE?
There were other aspects of the summit that engendered some discomfiture.
Sceptics have criticised the joint statement signed by both leaders at the close of the summit as being short on details, saying the summit in Singapore only helped to boost Mr Kim's international prestige.
A 42-minute-long film aired on Thursday by North Korean state television cemented this view for this group. The documentary depicted Mr Kim as "a prominent world leader" who was welcomed with "deep respect and boundless enthusiasm" in Singapore.
This has sparked unease among some Singaporeans, who ask if Singapore had played into North Korean propaganda.
Mr Shanmugam says he understands the unhappiness of those who object to Singapore hosting Mr Kim or Mr Trump, both of whom have their detractors.
"But you cannot conduct international diplomacy on that basis. You've got to ask yourself, is it in the country's interest. We cannot impose our moral standards personally on the leaders or on the countries. They didn't come on a bilateral visit to discuss issues with us; they came to talk to each other.
"We were a neutral venue and we have to behave like a neutral venue."
The minister adds that he believes the majority of Singaporeans support the hosting of the summit, which ended with the signing of a joint agreement in which both sides pledged to work towards complete denuclearisation of the Korean peninsula.
Friends from around the world had sent him e-mails gushing about Singapore's beauty, which they saw on TV and on the front pages of their countries' newspapers for a few days, he says.
For instance, a Bloomberg commentary called on both visiting leaders to learn from Singapore.
Some have tried to put a dollar value to the benefits of playing host, with media intelligence company Meltwater saying that Singapore might have gained over $700 million in exposure from the wall-to-wall coverage.
However, Mr Shanmugam, a former foreign minister, says: "The primary benefit is that we helped on the path to peace.
"That is in the interest of the world, it is in the interest of the region and specifically in the interest of Singapore. I don't think you can put a dollar value on that."
But he adds that all the publicity could potentially translate to increased tourism and business opportunities. In the international relations arena, it also "reaffirms our position as a serious country that people trust and rely upon as a serious player".
Ambassador-at-Large Tommy Koh shares this sentiment, telling Insight: "The publicity and goodwill generated is definitely worth more than the $20 million we spent in hosting the summit. It has enhanced Singapore's soft power.
"It is also an example of our successful diplomacy."
Some, too, have suggested that Singapore may benefit economically, if North Korea does open up one day, but that is a prospect too far away to contemplate.
For now, there are some new friendships forged - though even the details of that are, perhaps predictably, hazy.
Police Inspector (NS) Gim Joo Hyung, 25, who interpreted for the North Korean delegation, has been invited to Pyongyang to try "Pyongyang Naengmyeon", a cold buckwheat noodle dish that Mr Kim had taken to an earlier summit between North and South Korean leaders.
"When I was leaving and when they were leaving, they said, 'Next time, let's meet in Pyongyang.'"
On whether they exchanged contact details, he said no.
He quips: "I guess if I'm there, they would know."